Displaying 20 results from an estimated 1000 matches similar to: "Scheffé's method?"
2003 Nov 15
0
FW: computing a p-value ...
Thanks to Rolph Turner and Jason Turner ...
I guess I was too excited about getting back on the list after an absense of
several years ... I'll be a little more thoughtful about the problem before
posting next time, and a little less trigger-happy with the "Send" e-mail
button.
Never-the-less, much appreciated.
- Mohamed
-----Original Message-----
From: Rolf Turner
2012 Jun 25
2
Fractional Factorial - Wrong values using lm-function
Hello.
I'm a new user of R, and I have a question regarding the use of aov and
lm-functions. I'm doing a fractional factorial experiment at our production
site, and I need to familiarize myself with the analysis before I conduct
the experiment. I've been working my way through the examples provided at
http://www.itl.nist.gov/div898/handbook/pri/section4/pri472.htm
2012 Feb 02
9
Modelo senoidal de datos temporales de radiación y prueba de Thom
Hola a todos:
Estoy intentado realizar un modelo senoidal de unos datos de radiación
solar con el fin de afrontar el relleno de la serie y aplicar la prueba
de Thom para verificar su homogeneidad [0].
De momento me encuentro con los siguientes problemas:
1- ¿Existe la prueba de Thom en R? ¿O debo crearme mi propia función?
2- Para la realización del modelo senoidal estoy siguiendo los pasos
2006 Jul 30
2
NIST StRD linear regression
NIST maintains a repository of Statistical Reference Datasets at
http://www.itl.nist.gov/div898/strd/. I have been working through the
datasets to compare R's results to their references with the hope that
if all works well, this could become a validation package.
All the linear regression datasets give results with some degree of
accuracy except one. The NIST model includes 11 parameters,
2012 May 11
0
NLS sensitivity to start= values or poles in data range
Greetings R-help! I'm fairly new to R and am trying to expand my knowledge beyond using R for simple summary statistics and basic tests. To that end I am attempting to write an interactive R-script that will perform a general rational function fit to a given dataset based on the example given at http://www.itl.nist.gov/div898/handbook/pmd/section6/pmd64.htm.
The problem that I seem to have
2007 Jul 04
2
probabilty plot
Hi all,
I am a freshman of R,but I am interested in it! Those days,I am
learning pages on NIST,with url
http://www.itl.nist.gov/div898/handbook/eda/section3/probplot.htm,
I am meeting a problem about probability plot and I don't know how to
plot a data set with R.
Could somebody tell me the answer,and a example is the best! I will
look forward to your answer.
Thank you very much.
2005 Mar 23
2
R accuracy
Hello,
I am trying to test the precision of R on datasets from The Statistical Reference Datasets Project http://www.itl.nist.gov/div898/strd/index.html and I don't manage to understand how R is storing its results.
For example, I calculate a mean on the michelso dataset (100 values) and find:
> m=mean(michel)
> m
V1
299.8524
> print(m,digits=15)
V1
299.8524
2006 Mar 13
1
bihistogram plots
Does anyone have code to plot bihistograms in R?
See http://www.itl.nist.gov/div898/handbook/eda/section3/bihistog.htm
for a description of
a bihistogram.
--
Hal Varian voice: 510-643-4757
SIMS, 102 South Hall fax: 510-642-5814
University of California hal at sims.berkeley.edu
Berkeley, CA 94720-4600 http://www.sims.berkeley.edu/~hal
2002 May 01
1
"normal probability plot" with a percentile scale?
I'd like to generate some plots like you'd see on the old "normal
probability graph paper", like the first plot in:
<http://www.itl.nist.gov/div898/handbook/eda/section3/normprpl.htm>
except the horizontal scale would have 1%, 5%, 25%, 50%, 75%, 95%,
99%, or similar quantiles, with associated tick/grid lines. [still
hunting around for a good example...] something like
2012 May 04
3
read-in, error???
Dear Users!
I encountered with some problem in data reading while I challenged R (and
me too) in a validation point of view.
In this issue, I tried to utilize some reference datasets (
http://www.itl.nist.gov/div898/strd/index.html).
And the result departed a bit from my expectations. This dataset dedicated
to challenge cancellation and accumulation errors (case SmLs07), that's why
this
2006 Jul 14
2
References verifying accuracy of R for basic statisticalcalculations and tests
Hi,
> [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Corey Powell
>
> Do you know of any references that verify the accuracy of R
> for basic statistical calculations and tests. The results of
> these studies should indicate that R results are the same as
> the results of other statistical packages to a certain number
> of decimal places on some benchmark
2004 Apr 02
3
Single Factor Anova
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Hello all -
As I progress in R I am trying to automate functions I would have
normally farmed out to Excel, SPSS or Statistica. Single factor anova
is one of them. For example, a dataset from NIST StRD
(http://www.itl.nist.gov/div898/strd/anova/AtmWtAg.html) has two groups:
1 2
107.8681568 107.8681079
107.8681465 107.8681344
2003 Aug 15
2
help with Tukey Mean-Difference Plot
Dear R users,
I would appreciate for some advise how to generate a Tukey
Mean-Difference Plot with the tmd function part of the lattice
library. I have two test results (log transformed) which showing a
correlation on a scatterplot. However the correlation line is
parallel displaced depending on a clinical condition. I thought to a
Tukey Mean Difference Plot would show me the difference
2005 Jan 13
2
chisq.test() as a goodness of fit test
Dear R-Users,
How can I use chisq.test() as a goodness of fit test?
Reading man-page I?ve some doubts that kind of test is
available with this statement. Am I wrong?
X2=sum((O-E)^2)/E)
O=empirical frequencies
E=expected freq. calculated with the model (such as
normal distribution)
See:
http://www.itl.nist.gov/div898/handbook/eda/section3/eda35f.htm
for X2 used as a goodness of fit test.
Any
2003 Sep 04
0
SUMMARY: Comparison of SAS & R/Splus
My thanks to Drs. Armstrong, Bates, Harrell, Liaw, Lumley,
Prager, Schwartz, and Mr. Wang for their replies. I have
pasted my original message and their replies below.
After viewing http://www.itl.nist.gov/div898/strd/ as suggested
by Dr. Schwartz, it occurred to me that it might be educational
to search for some data repositories on google. I was able to find
some,though I'm sure many of
2008 Apr 17
2
Design and analysis of mixture experiments
Hi,
I'm interested in experimental design and data analysis on mixtures, like
cake recipes where the sum of the components is fixed; e.g.
<http://www.itl.nist.gov/div898/handbook/pri/section5/pri54.htm>.
I can't believe that R doesn't have facilities to design and analyse such
experiments, but I haven't been able to find them (I have looked quite
hard!). Can anyone point
2002 Jun 27
0
FW: re: GUI's for teaching
Have a look at the GUI on dataplot, NIST's plotting software. It is implemented in tcl/tk. The site states it is "public domain software" -- open source? I can't find anything about the license. In any case...
http://www.itl.nist.gov/div898/software/dataplot/
Brett A. Magill, Evaluator
Research, Assessment, and Evaluation
Saint Louis Public Schools
Brett.Magill at
2002 Jun 28
0
dataplot oen source? (was: RE: FW: re: GUI's for teaching)
IIRC, the license stated in the source code of dataplot is rather
restrictive. I don't think one is allowed to use the source as can be done
with GPL code.
Cheers,
Andy
> -----Original Message-----
> From: Brett A Magill [mailto:Brett.Magill at slps.org]
> Sent: Thursday, June 27, 2002 1:14 PM
> To: r-help at stat.math.ethz.ch
> Subject: [R] FW: re: GUI's for teaching
2005 Jan 21
0
R: chi-Squared distribution in Friedman test
Hi,
pchisq -> distribution function
dchisq -> density function
pval is the area under the curve, to calculte it you
use distribution function which is the integral of
density function. See:
http://www.itl.nist.gov/div898/handbook/eda/section3/eda362.htm
http://mathworld.wolfram.com/DistributionFunction.html
f(x) density function
F(x) distribution function =Pr(X<x)= integral(f(x))
2010 May 05
0
A question regarding the loess function
Hello,
I was hoping that someone familiar with the implementation details of the
loess algorithm might be able to help me resolve some difficulties I am
having. I am attempting to reproduce some of the functionality of the
loess() function in C++. My primary motivation is that I would like to
understand the algorithm in detail.
So far I have managed to create a working port in C++ for the